Sometimes users post questions in which
(1) mathematical terminology is used in grossly incorrect ways, and
(2) sentence structure is abominable, and
(3) grammar and spelling are quite bad, and
(4) nonetheless the meaning of the question is crystal-clear with next to no effort, and
(5) the posting clearly shows that the poster has thought about the question, and
(6) it clearly indicates at what point the poster had some difficulty with it, and
(7) it's just the kind of question that a good student learning the material ought to ask, and
(8) indicates what thoughts the poster had toward answering the question.
Among mathematicians who having been posting regularly to m.s.e. for a decade there are some (and they seem like a clique of about a dozen or two) who always vote to close the question, often avowing that it is incomprehensible or off topic or otherwise objectionable despite points (4) through (8) above.
Concerning one such question posted on December 26, matching points (1) through (8) perfectly, and that was closed and deleted on the grounds of its alleged incomprehensibility despite its perfect clarity, a respectable mathematician who is a professor with many publications, recently opined to me that he had difficulty understanding it. He differs from the "clique" above in that he is willing to communicate, and I know that he is honest. His claim that there is something difficult to understand in the question is incomprehensible to me, but his willingness to communicate, which is in such sharp contrast to that of the aformentioned "clique", convinces me that he is honest.
Here is a link to the question posted on December 26 (which some user here will not be able to see because it is deleted): https://math.stackexchange.com/questions/4342155/what-makes-a-number-big/4342169#4342169
Since some won't be able to see this, here is the whole question verbatim:
Limit to infinity of a function are explained as "the value of the function as $x$ gets really really big". My question is, what is big? Big and small are relative terms. So what makes a $x=1$ small and $x=100000$ big unless they are compared?
And here is my posted answer, with a net 6 upvotes and the O.P.'s acceptance:
$$ 5.1,\quad 5.01,\quad 5.001, \quad 5.0001, \ldots, \quad 5.\underbrace{000\ldots\ldots000}_{n \text{ 0s}} 1, \quad \ldots\ldots $$
The limit of the sequence as $n$ grows is $5.$
Loosely, one might say that that means it is very close to $5$ with $n$ is very big.
But more precisely, one can say that it can be made as close to $5$ as desired by making $n$ big enough. How big is big enough depends on how close one is to make the $n\text{th}$ term to $5.$
More precisely still: No matter how small the the distance one wants between the $n\text{th}$ term of this sequence and $5,$ there is a value of $n$ so big that the $n\text{th}$ term and all later terms will be within that distance from $5.$
Several persons in comments indicate that they understand the question (as expected), and one with a reputation of more than 50000 calls it "unclear" and "meaningless" and "[not] even about mathematics".
To me it is incomprehensible that a mathematician who has taught calculus, or probably even one who has not, would fail to find the meaning of the question crystal-clear, and it is not a lack of ability to understand such matters by which I achieved a reputation of more than a quarter million on m.s.e.
But it is even more incomprehensible that the members of this clique are unwilling to be minimally polite. They have been persistently unwilling to discuss things like this for about a decade—or maybe more. Their communications to me about these things consist of dogmatic assertions and orders to me to believe them and obey them. On many occasions over the past decade I have brought these matters to the attention of the moderators and they have never once replied. (In particular, there is nothing in this present posting of which the moderators have not been recently reminded.) Their persistent non-replies have been brought to the attention of the community managers several times, and they have also never replied.
Sometimes people post on subject matter of which I am ignorant, and I do not participate in what ensues. I do not complain that such questions are incomprehensible and meaningless and not about mathematics, and I do not order those who disagree with me to believe me and obey me when I say that.
Questions: Are there really mathematicians who can't understand questions like this one? Why? Why do they feel a need to order a contributor with a quarter-million reputation to believe and obey their assertions that something is incomprensible if they are not among those who understand it? Why are they unwilling to discuss anything, preferring instead to issue such orders?